The present invention relates to the field of medical devices, in particular electromagnetic stimulating devices for stimulation of nerve, muscle, and/or other body tissues with applications in the field of medicine.
The instant invention is drawn to an electromagnetic stimulating device able to provide stimulation to tissues of the human body, including nerves, muscles (including superficial and deep muscles), and/or other body tissues without significant discomfort to the patient. This electromagnetic stimulating device utilizes a plurality of overlapping planar coils encased in an ergonomic, body-contoured wrap. The design of the wrap is intended to allow for ease of use and also for the targeting of anatomic regions to be exposed to the impulses of the electromagnetic fields.
The device of the present invention provides an electromagnetic field to stimulate underlying body tissues in a manner necessary for the several applications including: the prevention/treatment of muscular atrophy, the treatment of neurogenic bladder and bowel, the treatment of musculoskeletal pain, the treatment of arthritis, and/or muscular augmentation. The plurality of overlapping coils are placed in an ergonomic wrap so as to blanket the designated therapeutic area, and thereby provide consistent therapy that can be quickly and easily administered. The invention is designed to be patient user friendly as well as to be portable. It can be used in a hospital, an outpatient clinic, a therapists office, or even at a patient""s home.
It is an object of the present invention to provide an electromagnetic device for stimulating regions of the body, which has overlapping coils which can be fired sequentially or in unison depending on the particular required treatment conditions requiring both maximal stimulation (sufficient to cause contraction of muscle fibers) as well as submaximal stimulation (which will be sufficient to provide therapy but not to cause contraction of muscle fibers). The applications of the device can be divided into maximal and submaximal categories, in which the former requires significantly higher levels of inducting current than the latter. The maximal applications of the device include: one, non-invasive stimulation of the peripheral nervous system; two, treatment and/or prevention of atrophy (as would be therapeutic during recovery after a persons sustains a fracture, experiences paralysis of a limb or other body part, or undergoes surgery, such as ACL repair in the knee; and three, treatment of neurogenic bladder and bowel. Submaximal applications of the device include: one, treatment of musculoskeletal pain (e.g. back and neck pain, muscle spasms, and other forms of muscle or skeletal related pain); and two, treatment of arthritis.
It is an object of the invention to provide a device for the electromagnetic stimulation of selective anatomic regions of the body, utilizing an ergonomic wrap to facilitate accurate and targeted placement of the device for the stimulation of key nerves, muscles, and/or body tissues.
It is an object of the invention to provide a device to electromagnetically stimulate selective nerves muscles, and/or body tissues that is user friendly and capable of being used even by an unskilled patient in a home healthcare setting.
It is an object of the invention to provide a device to electromagnetically stimulate selective nerves, muscles, and body tissues to provide consistent therapy, with the ergonomic wrap targeting key nerves and eliminating the requirement for a highly trained operator to manipulate the device.
The concept of pulsed electromagnetic stimulation was first observed by the renowned scientist Michael Faraday in 1831. Faraday was able to demonstrate that time varying, or pulsed electromagnetic fields have the potential to induce current in a conductive object. Faraday""s experimental setup was simple. He found that by passing strong electric current through a coil of wire he was able to produce pulsed electromagnetic stimuli. This pulsed electromagnetic stimulus was able to induce the flow of current in a nearby electrically conductive body.
In the years since the discoveries of Faraday, pulsed electromagnetic stimulators have found application in countless areas of scientific investigation. In 1965, the scientists Bickford and Freming demonstrated the use of electromagnetic stimulation to induce conduction within nerves of the face. Later, in 1982 Polson et al., U.S. Pat. No. 5,766,124 produced a device capable of stimulating peripheral nerves of the body. This device was able to stimulate peripheral nerves of the body sufficiently to cause muscle activity, recording the first evoked potentials from electromagnetic stimulation.
The ability of pulsed electromagnetic stimulation to induce electrical currents within tissues of the human body has prompted medical research in recent years with respect to the diagnosis, monitoring, and therapy of a variety of important conditions.
Electrical stimulation is a related technology that has been employed for man of years in the treatment of numerous medical conditions. One of the most commonly used for of electrical stimulation takes the form of what is known as TENS (Transcutaneous Electrical Nerve Stimulation) unit. These devices are designed specifically to stimulate nerve tissue that will block or interrupt pain signals being sent to the brain.
This class of electrical stimulating devices utilizes the principles of direct nerve stimulation to excite nerves. These technologies place electrodes directly on the skin or on occasions beneath the skin in a surgically implanted fashion. The electrodes carry wires, through which electrons flow and create a transfer of charge to the tissues and nerve cells beneath.
Electrical stimulation can be effective in stimulating superficial tissues, as stimulation is usually accomplished from small electrodes, with moderate voltage and current levels. Electrical stimulation, however, can cause significant skin irritation and burns as has been reported in a significant number of cases within the medical literature (Balmmaseda M T , et al. Burns in functional electric stimulation. Archives of Physical Medicine and Rehabilitation. July 1987; 68(7)452-53). In its alternative forms, such as with surgically implanted electrodes, electrical stimulation can be invasive and consequently associated with adverse side effects. The difficulties with electrical stimulation become especially significant as large excitation levels are required for more complete stimulation of nerves.
The limitations of electrical stimulation have prompted investigations into the possible applications of pulsed electromagnetic stimulation. The basic principal behind the concept of electromagnetic stimulation is that an electric current pulsed, or passed through a coil winding structure will generate an electromagnetic field. An electromagnetic field can, in turn, generate a current in any conductive material, such as nerves or other body tissues, within this field.
The electromagnetically induced electric field created by properly oriented pulsed electromagnetic stimulation thus accomplishes the result of transferring charge to cells of the body. This transferred charge can lead to nerve firing, muscle contraction, stimulation of cell signaling pathways causing cell growth, and a number of other effects.
In contrast to applications of electrical stimulation, pulsed electromagnetic stimulation does not require direct skin contact to induce nerve excitation. As a result, significantly higher levels of directed stimulation can be achieved though pulsed electromagnetic stimulation without the adverse effects of other technologies.
The ability of electromagnetic stimulation to induce electrical currents within tissues of the human body has prompted medical research in recent years with respect to the diagnosis, monitoring, and therapy of a variety of conditions, including: preventing and treating muscle atrophy, treating neurogenic bowel and bladder, offering pain control for musculoskeletal and back pain, and treating arthritis.
The device of the present invention is a powerful electromagnetic stimulating device created for the purpose of stimulating nerve, muscle, and/or other body tissues. The device builds on existing electromagnetic stimulator technology to provide an easy-to-use, ergonomically designed system that will have applications within a host of clinical and home ease of use health applications.
One of the earliest applications of electromagnetic stimulating technology took the form of bone growth stimulators. These devices employ low frequency pulsed electromagnetic fields to stimulate bone repair. Bone growth stimulators first found use approximately 20 years ago in the treatment of non-healing fractures, and are slowly becoming the standard of care for this condition.
As investigators have studied the effects of electromagnetic fields on fracture healing, it has been demonstrated that low frequency pulsed electromagnetic fields can not only facilitate fracture healing but also cause the growth of cartilage cells (Rheumatic Diseases Clinics of North America, 26(1):51-63, February 2000). This ability to stimulate new cartilage growth creates a tremendous potential for treating arthritis.
The effects electromagnetic fields on the repair of cartilage and soft fibrous tissues have been demonstrated in a number of recent studies. Pulsed electromagnetic devices have been shown to be effective in treating patients with chronic knee arthritis, demonstrating that this treatment effective in the reducing pain and improving function. (Rheumatic Diseases of Clinics of North America, 26(1)52-63, February 2000).
Not only has electromagnetic stimulation been shown to improve repair of cartilage and soft tissues, it has also been shown to be safe and cost-effective for treating patients with chronic knee pain due to arthritis (Altern Ther Health Med, 7(5):54-64, September-October 2001). The treatment has not been demonstrated to have any side effects and may be useful in forestalling joint replacements.
The present invention also provides a simple, noninvasive solution to the problem of neuropathic bladder and rectum, such as persons with spinal cord injuries or Multiple Sclerosis might experience. Just as these persons may have paralysis of the arms or legs, they can also have a so-called xe2x80x9cparalysisxe2x80x9d of the bladder and bowel, with associated difficulty emptying the bladder and bowels. Complications that can arise from neurogenic bladder and bowel are significant. In mortality studies of persons with spinal cord injuries, after a period of high mortality at the time surrounding the initial injury, neurogenic bladder has been shown to be the primary cause of death among persons with spinal cord injuries.
Invasive methods have been attempted to address this problem but without significant success. In animal models electromagnetic stimulation has been shown to increase bladder and bowel pressures, and to thereby effect evacuation (Urology, 54(2) 368-72, August 1999). This technique is simple, safe, noninvasive, and has no known adverse effects.
The present invention also provides a treatment for one of the major causes of stress urinary incontinencexe2x80x94a condition referred to as xe2x80x98idiopathic detrusor instability.xe2x80x99 Detrusor instability describes the unstable contractions of the detrusor muscle (a muscle controlling the release of urine from the bladder), which can cause persons to lose, or be incontinent of urine. Studies have shown that electromagnetic stimulation of sacral (an area of the lower spine) nerve roots acutely abolishes unstable contractions in patients with this condition (British Journal of Urology, 80(5):734-41, November 1997).
The prior art devices provide electromagnetic stimulators, which utilize pulse electromagnetic fields to promote positive effects on the human body. These effects have been well-established in multiple large, double-blind, placebo-controlled studies in the medical literature. The device of the present invention substantially improves the state-of-the-art electromagnetic stimulation technology and incorporates it into a user-friendly, body-contoured applicator with multiple overlapping coils to effectively carpet the entire targeted subcutaneous region.
Considered as a group, existing electromagnetic stimulators cannot be operated by the patient but require a skilled technician. These devices employ a single, focused coil of varying configurations to provide electromagnetic induction. While this may be practical for diagnostic purposes, it is not user friendly or cost-effective for the treatment of muscle atrophy, neurogenic bladder and bowel, musculoskeletal pain, arthritis, and a host of other conditions.
There have been limited attempts in the prior art to solve the existing problems associated with the use of electromagnetic stimulation devices. One such example of electromagnetic stimulation is described in U.S. Pat. No. 6,086,525 issued to Davey et al. Davey discloses a device that has a single coil in the shape of a xe2x80x9cCxe2x80x9d where the intensity of the electromagnetic field is between the ends of the xe2x80x9cCxe2x80x9d. That point must be employed directly over the target nerve or muscle to be stimulated. The coil is toroidal in configuration and utilizes a unique core of vanadium permendur in the preferred form. One of the disadvantages of this device is that it requires a trained technician to treat the patient and to properly hand hold the open end of the xe2x80x9cCxe2x80x9d over the targeted nerve or muscle to be stimulated. The device is not portable and is designed for use in hospitals or similar institutions. Also the vanadium permendur core is required to increase the strength of the electromagnetic field to be strong enough to be effectively used. The design, shape and configuration described in Davey and other prior art devices, require the electromagnetic stimulator to be hand operated during use.
Further, Davey is specifically designed to discourage secondary stimulation sites. It is intended to focus and concentrate the field to a single point. However, for therapeutic use the nerves and muscles that need stimulation are not located at a singe point but in a larger area and hence the focus of the field needs to radiate to a larger area and not be isolated to a single point. In fact secondary muscle stimulation is necessary for proper treatment in many applications.
The present invention eliminates the need to have a trained technician conduct the electromagnetic stimulation by providing an ergonomic wrap that encases the overlapping coils. The wrap with reference indica is designed to enable an unskilled patient to properly place the wrap such that the proper key nerves, muscles, and/or other body tissues are stimulated A trained physician will prescribe the planned degree of electromagnetic stimulation required, both in time and intensity.
The use of a solid core is also required in Davey to generated sufficient electromagnetic field intensity to stimulate the nerves, muscles, and/or other body tissues. The Present invention overcomes the need for a solid core by providing overlapping coils that electrically amplify the intensity of the electromagnetic field so as to stimulate the nerves, muscles, and/or other body tissues. Also since no solid core is required in the present invention the overlapping coils can be planar and disposed within a flexible ergonomic body wrap that is not contemplated or possible using the devices of the prior art. The plurality of overlapping coils also provides an appropriate area of intense electromagnetic stimulation to bathe the nerves, muscles, and/or body tissues more thoroughly than any of the existing single coils devices.
The present invention proposed a separate flexible wrap designed for each part of the body to be treated. Each such body wrap has marking indicia that enable an untrained patient to properly locate the stimulation coils to effectively treat that specific area of body. No skilled technician need be used in the treatment. The devices of the prior art cannot be used in a flexible body wrap because of the necessity to utilize a solid single core.
Hence, the device of the present invention permits the planar coils to be used in a flexible body wrap, not contemplated or possible by any prior art device. The overlapping coils create an amplified electromagnetic field to stimulate nerves, muscles, and/or other body tissues without the use of using a solid core. These advancements are not taught or contemplated by the prior art and produce an unexpected increase in the electromagnetic field intensity capable of stimulating nerves, muscles, and/or other body tissues. As such the overlapping coils can be placed in a flat plane (or in a contoured plane surrounding a particular part of the body), or disposed in an ergonomic flexible body wrap also not contemplated by the prior art devices.